UNUTILIZED POTENTIAL OF TRUE SERVICE TREE (SORBUS DOMESTICA L.)

In Slovakia there is a small population of true service tree (Sorbus domestica L.). Experimental studies enabled an evaluation of economic value of this population. By territorial monitoring, 167 genotypes in 17 localities have been detected and 139 trees have been selected for the study. In every case, an exact geographical position was measured using GPS equipment. The genotypes found occurred in altitudes of 200 to 650 m above sea level; only a few of trees were found above 600 m. For every genotype, image documentations of tree, buds, flowers, leaves, fruits and seeds were created and used for comparative studies of qualitative traits. For all genotypes, we measured the height (5-23 m) and width of crown (4-21.5 m). The medium weight, length and width of fruits were calculated from intervals (4.91-18.64 g, 19.84-36.29 mm and 18.9-32.58 mm, respectively). A new list of descriptors was developed, thus enabling an evaluation of traits and characterization of true service tree genetic resources. We proposed 28 fully new descriptors and 26 original descriptors that have been revised. Chemical analyses have been used in fruits to detect 14-16% sucrose and 1.2-1.8% vitamin C. Pulp share on total fruit ratio was 86%. The nutritional value of the fruit is excellent, as there are several easily utilizable mono-saccharides, carbohydrates and organically bound metal ions present. In our studies it was found that the cation content of service tree fruits is higher than in apples or pears, e.g., there are 3-4 times more potassium and calcium in true service tree fruits. Data collected on true service tree genotypes were catalogued according to the new list of descriptors. This specialized information system could be used for evaluation and registry of true service tree genetic resources using updated information and communication technologies. Fruits, seeds and wood of true service tree can be widely used for food production, pharmaceutics, cosmetics, landscaping, craftsmanship and other branches.